Metro Core Network

A parallel evolutionary trend to 5G is software virtualization and cloud services, where the core network is implemented onto a distributed set of data centers that provide service agility, centralized control, and software upgrades. SDN, NFV, cloud, and open ecosystems are likely to be the foundations of 5G and there is an ongoing discussion about how to take advantage of these into new network architectures.

An adaptive network solution framework will become a necessity for interfacing with both LTE and new air interface evolution: Cloud, SDN and NFV technologies will reshape the entire mobile network design principles. As the three-tier hierarchy (access, forwarding, and control) of network architecture is being replaced by flatter architectures, virtualized application software is replacing discrete network elements, and network infrastructure is becoming more ‘programmable’. With SDN the network will dynamically adapt itself to provide the connectivity services that best serve the application, and a better approach will eventually produce networks that are much more flexible in providing new services and monetizing the network, as well as being more efficient in their use of resources. Such a capability is now being introduced under the concept of network “slicing”, where a slice is made across the different domains of the network to configure for a specific service.

Network Function Virtualization (NFV) works by virtualizing into software the roles of the various network function elements into a series of Virtual Network Functions (VNF). These different VNFs run on standardized hardware (servers), leading to the virtualization of the physical network infrastructure that provides a seamless deployment. VNFs are then linked together to provide a specific service for the customer, using service chaining which is configured, managed, and monitored through the operators service orchestration function. Service providers can now integrate this optimized virtual infrastructure with their service orchestration systems. This allows them to integrate their OSS/BSS implementation for dynamic routing, billing and delivery of services.